Originally Posted by cccapt
Nothing except the color of the bulb. I use 4 regular flourescent bulbs, 2 being 65K daylight bulbs and 2 Actinic o3 bulbs.
Ah, so we're paying a premium for those external ballast & starter units then?? 8O
Although the pet shop I was at yesterday has a few 2nd hand ones in a "Everything £3.99 this box" for sale, might make setting up my river tank a little bit cheaper....